Scanner device and multifunction apparatus including the same

ABSTRACT

A scanner device including: a scanning path on which a scanning member for scanning an image from a document is disposed; a supply path on which a document is supplied to the scanning path; a discharge path on which a document is discharged after scanning of the document on the scanning path has been completed; and a re-supply path that extended to the supply path from a intersection where the scanning path and the discharge path cross so that a document fed along the discharge path in a direction opposite to a document-feeding direction is re-supplied to the supply path after scanning of one side of the document has been completed, wherein one-side guide portions of the supply path, the discharge path, and the re-supply path are integrally formed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/547,768, filed on Jul. 12, 2012, which is currently pending, andclaims the benefit of Korean Patent Application No. 10-2011-0069497,filed on Jul. 13, 2011, in the Korean Intellectual Property Office, thedisclosures of each of which are incorporated herein in their entiretyby reference.

BACKGROUND

1. Field

The present invention relates to a scanner device that scans an imagefrom a document and a multifunction apparatus including the same.

2. Description of the Related Art

Scanner devices irradiate light onto a document and receive lightreflected from the document, thereby reading an image formed on thedocument. Scanner devices use scanning methods, such as a flatbedscanning method in which a document is put in a fixed position and animage is read when a scanning member, such as a contact type imagesensor (CIS), a charge coupled device (CCD), or the like, is moved, adocument-feeding scanning method in which a scanning member is disposedin a fixed position and a document is fed, and a composite scanningmethod thereof.

Scanner devices may be configured as a single device or a multifunctionapparatus that is combined with a printer including a printing unit forprinting an image on a sheet of paper, or combined with a copy machine.

Scanner devices include a plurality of components for forming a feedpath on which a document is fed and for accommodating an actuatordetecting the document and a sensor that is operable by the actuator. Asa number of components for forming the feed path increases, the feedpath may become less uniform, a document-feeding performance may belowered, and assembling cost may be increased. In addition, as thelength of connection lines for electrically connecting sensors and acontrol unit increases, manufacturing cost increases.

SUMMARY

Additional aspects and/or advantages will be set forth in part in thedescription which follows and, in part, will be apparent from thedescription, or may be learned by practice of the invention.

The embodiments of the present disclosure provides a scanner device thatmay reduce a document-feeding defect caused by an assembling error byreducing the number of components for forming a document-feeding path,and a multifunction apparatus including the scanner device.

The embodiments of the present disclosure also provides a scanner devicethat may reduce the length of connection lines for electricallyconnecting sensors and a control unit, and a multifunction apparatusincluding the scanner device.

According to an embodiment, there is provided a scanner deviceincluding: a scanning path on which a scanning member for scanning animage from a document is disposed; a supply path on which a document issupplied to the scanning path; a discharge path on which a document isdischarged after scanning of the document on the scanning path has beencompleted; and a re-supply path that extended to the supply path from anintersection where the scanning path and the discharge path cross sothat a document fed along the discharge path in a direction opposite toa document-feeding direction is re-supplied to the supply path afterscanning of one side of the document has been completed, whereinone-side guide portions of the supply path, the discharge path, and there-supply path are integrally formed.

The one-side guide portions of the supply path, the discharge path, andthe re-supply path may be integrally formed by using injection molding.

The scanner device may further include an upper frame, a base frame, anda main frame interposed between the base frame and the upper frame. Themain frame may be integrally formed with the one-side guide portions ofthe supply path, the discharge path, and the re-supply path by usingplastic injection molding.

The one-side guide portions may include a lower supply guide portion, alower discharge guide portion, and a lower re-supply guide portionforming lower guides of the supply path, the discharge path, and there-supply path, respectively.

The upper frame may include an upper guide portion that faces the firstre-supply guide portion and the first discharge guide portion and formsthe re-supply path and the discharge path, and an upper supply guideportion that faces the lower supply guide portion and forms the supplypath.

An end part of the lower re-supply guide portion that is directedtowards the discharge path may be stepped from an end part of the lowerdischarge guide portion that is directed towards the re-supply path sothat a document fed along the discharge path in a direction opposite toa document-feeding direction is guided to the re-supply path.

The scanner device may further include a pressing member for pressing adocument against the scanning member. The pressing member may bedisposed facing a scanning window in a position above the scanningmember so that the document is secured in contact with the scanningwindow, and forms an upper guide of the scanning path.

The scanner device may further include at least one actuator that isrotated in contact with a fed document, and at least one document sensorfor detecting rotation of the actuator and generating an electricalsignal. The at least one document sensor may be disposed in a regionoutside of a document-feeding region in a widthwise direction of adocument.

The scanner device may further include a control unit for controlling anoperation of feeding a document. The control unit may be disposed in theregion outside of the document-feeding region.

The scanner device may further include a main frame integrally formedwith the one-side guide portions of the supply path, the discharge path,and the re-supply path by using plastic injection molding. At least oneof the at least one document sensor may be disposed in a sidewall of themain frame in the region outside of the document-feeding region.

According to another aspect of the present disclosure, there is provideda multifunction apparatus including: the aforementioned scanner device;and a printing unit for printing an image on a sheet of paper.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIG. 1 is a cross-sectional view of a document-feeding path of a scannerdevice according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a document-feeding unit and adocument-detecting unit of the scanner device illustrated in FIG. 1;

FIG. 3 illustrates an operation of separating a plurality of documentsfrom one another by using an automatic document feeding (ADF) roller anda separation member of the scanner device of FIG. 1;

FIG. 4 is a perspective view of an example of a main frame of thescanner device of FIG. 1;

FIG. 5 illustrates an example of a structure for guiding a document ontoa re-supply path so as to perform both-side scanning;

FIGS. 6 and 7 are perspective views of the document-detecting unit ofFIG. 2;

FIG. 8 is a plane view illustrating a position where a document sensorand a control unit are disposed;

FIG. 9 is a cross-sectional view of a structure of a multifunctionapparatus according to an embodiment of the present invention; and

FIG. 10 is a cross-sectional view illustrating a state where anautomatic document feeding unit is rotated so as to perform flatbedscanning by using the multifunction apparatus illustrated in FIG. 9.

DETAILED DESCRIPTION

The present invention will now be described more fully with reference tothe accompanying drawings, in which exemplary embodiments of theinvention are shown.

FIG. 1 is a cross-sectional view of a document-feeding path of a scannerdevice 100 according to an embodiment of the present invention.Referring to FIG. 1, the scanner device 100 may include an automaticfeeding unit 200 and a scanning unit 300.

The scanning unit 300 includes a scanning member 310 for reading animage from a document. The scanning member 310 irradiates light onto thedocument and receives light reflected from the document, thereby readingthe image formed on the document. The scanning member 310 may be acontact type image sensor (CIS), a charge coupled device (CCD), or thelike.

The scanner device 100 illustrated in FIG. 1 uses a composite scanningmethod in which both a flatbed scanning method and a document-feedingscanning method are used. The scanning unit 300 further includes aplaten glass 320 on which the document is disposed, so as to read theimage from the document by using the flatbed scanning method. Thescanning unit 300 further includes a scanning window 330 through whichthe image is read from the document by using the document-feedingscanning method. The scanning window 330 may be a transparent member,for example. The height of a top surface of the scanning window 330 maybe the same as that of a top surface of the platen glass 320.

When the document-feeding scanning method is used, the scanning member310 is disposed under the scanning window 330. When the flatbed scanningmethod is used, the scanning member 310 may be moved by a movement unit(not shown) in an auxiliary scanning direction, i.e., in a lengthwisedirection of the document, under the platen glass 320. In addition, whenthe flatbed scanning method is used, the automatic feeding unit 200 maybe rotated with respect to the scanning unit 300, as illustrated in FIG.10, so that the document may be put on the platen glass 320.

The automatic feeding unit 200 feeds the document so that the scanningmember 310 may read the image formed on the document and discharges thedocument after the image has been scanned. Referring to FIG. 1, theautomatic feeding unit 200 may include a scanning path 702 on which theimage is scanned by the scanning member 310, a discharge path 703 onwhich the document is discharged after the image has been scanned, and asupply path 701 on which the document is supplied to the scanning path702. In order to perform both-side scanning, the automatic feeding unit200 may further include a re-supply path 704 for guiding the documentfed along the discharge path 703 in a direction opposite to adocument-feeding direction to the scanning path 702 after scanning ofone side of the document has been completed.

Referring to FIG. 1, when one-side scanning is performed, the documentis discharged in the order of the supply path 701, the scanning path702, and the discharge path 703. Referring to FIG. 2, when both-sidescanning is performed, before the document fed to the discharge path 703is fully discharged after scanning of one side of the document has beencompleted, the document is fed along the discharge path 703 in thedirection opposite to the document-feeding direction and passes throughthe scanning path 702 via the re-supply path 704 and the supply path701. The document is discharged via the discharge path 703 afterscanning of both sides of the document has been completed.

The automatic feeding unit 200 may include a base frame 410, an upperframe 430, and a main frame 420 interposed therebetween. The main frame420 includes a lower re-supply guide portion (first re-supply guideportion) 724 that forms a lower guide of the re-supply path 704. Themain frame 420 further includes a lower discharge guide portion (firstdischarge guide portion) 723 that forms a lower guide of the dischargepath 703. The main frame 420 further includes a lower supply guideportion (first supply guide portion) 721 that forms a lower guide of thesupply path 701.

The upper frame 430 includes an upper guide portion 734 that faces thelower re-supply guide portion 724 and the lower discharge guide portion723 to form the re-supply path 704 and the discharge path 703. The upperframe 430 further includes an upper supply guide portion (second supplyguide portion) 731 that faces the lower supply guide portion 721 to formthe supply path 701.

Referring to FIG. 1, the upper frame 430 further includes an upper cover431 that forms the exterior of the scanner device 100, and a guide frame432 that is combined with a lower side of the upper cover 431. The upperguide portion 734 may have a plurality of rib shapes, for example,arranged on the guide frame 432 in a widthwise direction (depthdirection in FIG. 1) of the document. The upper supply guide portion 731may have a plurality of rib shapes arranged on the upper cover 431 inthe widthwise direction (depth direction in FIG. 1) of the document.

The scanner device 100 further includes a document-feeding unit thatfeeds the document. Referring to FIG. 2, the document-feeding unitincludes a supply portion 610 that feeds the document supplied from aloading stand 440 to the supply path 701, a main feeding portion 620that is disposed between the supply path 701 and the scanning path 702and feeds the document to the scanning path 702, an auxiliary feedingportion 630 that feeds the document passed through the scanning path 702to the discharge path 703, and a discharge portion 640 that is installedon the discharge path 703 and discharges the document. The dischargeportion 640 may feed the document in the direction opposite to thedocument-feeding direction, thereby feeding the document to there-supply path 704. The document, after being passed through there-supply path 704, is fed by the supply portion 610 to the supply path701.

The supply portion 610, the main feeding portion 620, the auxiliaryfeeding portion 630, and the discharge portion 640 may each include adriving roller and a driven roller engaged to each other and rotatedwith respect to each other. The driving roller is a roller that isrotated due to power supplied by a power source (not shown), and thedriven roller is a roller that is engaged with the driving roller and isrotated by the driving roller.

The automatic feeding unit 200 according to the current embodiment mayperform automatic document feeding (ADF) in which one document is takenout from a plurality of documents and is supplied to the supply path701. To perform this, as shown in FIGS. 2 and 3, the upper frame 430 mayinclude an ADF roller 650 and a separation member 660 that faces the ADFroller 650. The separation member 660 may be elastically biased by anelastic member 670 towards the ADF roller 650. The ADF roller 650 andthe separation member 660 may separate one document from the pluralityof documents by using differences in frictional forces between thedocuments, the ADF roller 650, and between the documents and theseparation member 660, for example. When the plurality of documents areput between the ADF roller 650 and the separation member 660, thefrictional force between the documents is smaller than the frictionalforce between the ADF roller 650 and the documents and the frictionalforce between the separation member 660 and the documents. Thus, only adocument that contacts the ADF roller 650 may be separated from thedocuments by being slid off the plurality of documents and fed by thesupply portion 610 to the supply path 701.

FIG. 4 is a perspective view of an example of the main frame 420.Referring to FIG. 4, the main frame 420 has an approximately H-shapedmember including both sidewalls 421 and 422 and first and secondconnection portions 423 and 424 that connect the sidewalls 421 and 422to each other and that extend in a horizontal direction, i.e., in thewidthwise direction of the document. The main frame 420 may bemanufactured by using plastic injection molding, for example. The firstand second connection portions 423 and 424 are spaced apart from eachother in the document-feeding direction, i.e. a direction perpendicularto the widthwise direction of the document.

For example, the lower re-supply guide portion (see 724 of FIG. 1) maybe configured by an upper surface of the first connection portion 423.According to the current embodiment, a plurality of ribs 425 arearranged on the upper surface of the first connection portion 423 andprotrude from the first connection portion 423 and are spaced apart fromeach other in the widthwise direction of the document. The lowerre-supply guide portion 724 is configured by the plurality of ribs 425.Thus, a frictional force that may be generated between the firstconnection portion 423 and the document may be reduced due to the lowerre-supply guide portion 724. For example, the lower discharge guide (see723 of FIG. 1) may be configured by an upper surface of the secondconnection portion 424. According to the current embodiment, a pluralityof ribs 426 are arranged on the upper surface of the second connectionportion 424 and protrude from the second connection portion 424 and arespaced apart from each other in the widthwise direction of the document.The lower discharge guide 723 is configured by the plurality of ribs426. The lower supply guide portion (see 721 of FIG. 1) may beconfigured by a plurality of ribs 427 that protrude from a bottomsurface of the first connection portion 423 and are spaced apart fromone another in the widthwise direction of the document.

Referring to FIG. 1, the scanning path 702 may be configured by thescanning window 330 disposed on the scanning unit 300, and a pressingmember 740 that is disposed facing the scanning window 330 in a positionabove the scanning window 330. The pressing member 740 forms an upperguide of the scanning path 702. The pressing member 740 may be installedat the main frame 420. The pressing member 740 presses the documentagainst the scanning member 310 so that the document may be secured incontact with the scanning window 330. The pressing member 740 isinstalled at the main frame 420 in a vertical direction. The pressingmember 740 may press the document against the scanning member 310 due tothe weight of the pressing member 740. In addition, an elastic member750 may be disposed above the pressing member 740 so that the pressingmember 740 presses the document against the scanning member 310. Asurface of the pressing member 740 that faces the scanning member 310may be white so as to provide a criterion for white balance of thescanning member 310. In addition, a white sheet (not shown) forproviding the criterion for white balance may be attached to the surfaceof the pressing member 740 that faces the elastic member 750.

A discharge guide portion 411 is disposed on the base frame 410 so as toguide the document to the discharge path 703 after the document haspassed through the scanning path 702.

As described above, in the scanner device 100 illustrated in FIG. 1,one-side guide portions 721, 723, and 724 of the supply path 701, thedischarge path 703, and the re-supply path 704 are integrated with themain frame 420, and the other-side guide portions 731 and 734 of thesupply path 701, the discharge path 703, and the re-supply path 704 areformed on the upper frame 430. According to this configuration, degreesof precision of positions of the supply path 701, the discharge path703, and the re-supply path 704 and gaps of both guide portions of eachof the supply path 701, the discharge path 703, and the re-supply path704 depend on manufacturing errors of the upper frame 430 and the mainframe 720 and an assembling error therebetween. Thus, the number offactors for determining the degrees of precision of the supply path 701,the discharge path 703, and the re-supply path 704 may be minimized.Thus, a document-feeding defect that is caused by the lowered degrees ofprecision of the supply path 701, the discharge path 703, and there-supply path 704 may be reduced. In addition, the one-side guideportions 721, 723, and 724 of the supply path 701, the discharge path703, and the re-supply path 704 are integrated with the main frame 420and thus the number of components of the scanner device 100 may bereduced and material cost may be reduced.

Referring to FIG. 5, an end part 725 of the lower re-supply guideportion 724 that is directed towards the discharge path 703 is steppeddownward from an end part 726 of the lower discharge guide portion 723that is directed towards the re-supply path 704. The document haspredetermined rigidity. A rear end of the document remains straight dueto the rigidity of the document as the document is being dischargedalong the discharge path 703 by the discharge portion 640. Thereafter,when the discharge portion 640 feeds the document in the directionopposite to the document-feeding direction, the document is not directedtowards the scanning path 702 but is directed towards the re-supply path704 due to a stepped amount S. According to this configuration, thedocument may be guided to the re-supply path 704 after being fed by thedischarge portion 640 in the direction opposite to the document-feedingdirection along the discharge path 703. Thus, an additional guide memberfor guiding the document discharged from the scanning path 702 to thedischarge path 703 and guiding the document fed in the directionopposite to the document-feeding direction along the discharge path 703to the re-supply path 704 is not required and thus material cost may bereduced and a document-feeding defect caused by an operational defect ofthe guide member may be prevented.

The scanner device 100 may further include a document-detecting unitthat detects the existence and position of the document and whether thedocument has been discharged. For example, referring to FIG. 2, thescanner device 100 illustrated in FIG. 1 may include a first detector801 that detects whether the document is loaded on the loading stand440, a second detector 802 that detects whether the document is fed tothe scanning path 702, and a third detector 803 that detects whether thedocument has been discharged via the discharge path 703.

FIG. 6 illustrates an example of the first detector 801. Referring toFIG. 6, the first detector 801 includes an actuator 810 that ismechanically operated by the document, and a document sensor 820 thatdetects whether the actuator 810 is operating and generates anelectrical signal. The actuator 810 may be rotatably installed at theupper cover 431, for example. The actuator 810 may include a rotationshaft 811, an interference portion 812, and an operational portion 813.The rotation shaft 811 extends in the horizontal direction, i.e., thewidthwise direction of the document, and is rotatably supported by theupper cover 431. The interference portion 812 extends in a downwarddirection from the rotation shaft 811 so as to interfere with thedocument loaded on the loading stand 440. The operational portion 813extends from the rotation shaft 811 and allows the document sensor 820to operate. For example, the document sensor 820 illustrated in FIG. 6is a photointerruptor sensor including an emitter 821 and aphotodetector 822. When an optical path between the emitter 821 and thephotodetector 822 is interrupted by the operational portion 813, lightis not detected by the photodetector 822, and when the operationalportion 813 escapes from the optical path, light is detected by thephotodetector 822. Thus, the document sensor 820 generates an off signalor an on signal according to the position of the operational portion813. The on signal and the off signal may be signals having differentvoltage levels, for example. Alternatively, the document sensor 820 mayhave any of other shapes as long as the document sensor 820 operates dueto the operational portion 813 and generates electrical signals havingdifferent voltage levels. For example, the document sensor 820 may be amicro-switch sensor that is turned on/off due by the operational portion813.

When the document is not loaded on the loading stand 440, theoperational portion 813 interrupts the optical path. Thus, the documentsensor 820 generates an off signal, for example. As illustrated in FIG.7, when the document is loaded on the loading stand 440, theinterference portion 812 is pushed by a front end of the document, andthe actuator 810 is rotated around the rotation shaft 811 in a directionA. Then, the operational portion 813 escapes from the optical path ofthe document sensor 820. Thus, light is detected by the photodetector822, and the document sensor 820 generates an on signal, for example.Thus, the document sensor 820 may detect whether the document is loadedon the loading stand 440.

The structure of the second detector 802 may be the same as that ofFIGS. 6 and 7. The only difference therebetween is that the rotationshaft 811 is rotatably supported on a lower portion of the main frame420 and the interference portion 812 is disposed across the scanningpath 702 so as to interfere with the document fed to the scanning path702. The front end of the document fed to the scanning path 702 may bedetected by the second detector 802, and a scanning starting time may bedetermined by the scanning member 310.

The structure of the third detector 803 may also be the same as thestructure of FIGS. 6 and 7. The only difference therebetween is that therotation shaft 811 is rotatably supported on the guide frame 432 and theinterference portion 812 is disposed across the discharge path 703 so asto interfere with the document fed to the discharge path 703. The rearend of the document fed to the scanning path 702 may be detected by thethird detector 803, and the third detector 803 may determine whether thedocument has been discharged. In addition, after the rear end of thedocument is detected during both-side scanning, the document may be fedin the direction opposite to the document-feeding direction by using thedischarge portion 640 and thereby may be fed to the re-supply path 704.

As illustrated in FIGS. 6 and 7, the rotation shaft 811 of the actuator810 extends in the widthwise direction of the document from theinterference portion 812, and the operational portion 813 is disposed onan end part of the rotation shaft 811 opposite to the interferenceportion 812. FIG. 8 is a schematic plane view of the scanner device 100illustrating a document-feeding region W and a position where thedocument sensor 820 is installed. The interference portion 812 needs tointerfere with the document and thus is disposed in the document-feedingregion W. The rotation shaft 811 extends in the widthwise direction ofthe document from the interference portion 812 up to a region W2 outsideof the document-feeding region W, and the operational portion 813 isdisposed on an end part of the rotation shaft 811. The document sensor820 may be installed at the sidewall 422 of the main frame 420.According to this configuration, since a structure for installing thedocument sensor 820 is disposed outside the document-feeding region W,the structure of the main frame 420 and the upper frame 430 may besimplified. In other words, a structure that disturbs thedocument-feeding path may not be formed in portions of the main frame420 and the upper frame 430 that correspond to the document-feedingregion W and thus a document-feeding defect may be reduced.

FIG. 8 illustrates a control unit 900 that controls a document-feedingoperation. The control unit 900 may be installed at the outer region W2.For example, the control unit 900 may be installed at the base frame410. The document sensor 820 is electrically connected to the controlunit 910 via connection lines 830. According to the scanner device 100illustrated in FIG. 1, the structure for installing the document sensor820 is disposed in the outer region W2 outside the paper feeding regionW. Thus, since the connection lines 830 do not pass through thedocument-feeding region W, a structure for guiding the connection lines830 does not need to be formed in the portions of the main frame 420 andthe upper frame 430 that correspond to the document-feeding region W.Thus, the shapes of the main frame 420 and the upper frame 430 may besimplified, and a structure that disturbs the document-feeding path isnot formed in the document-feeding region W and thus thedocument-feeding defect may be reduced. In addition, since the documentsensor 820 is disposed in the outer region W2, a distance between thedocument sensor 820 and the control unit 900 is shorter than that in acase where the document sensor 820 is disposed in the document-feedingregion W. Thus, the length of the connection lines 830 may be reduced.Thus, material cost may be reduced, and a process of arranging theconnection lines 830 is simplified, and process cost may be reduced. Inaddition, since the connection lines 830 having a short length are used,a problem, such as electromagnetic interference or the like, may bereduced.

FIGS. 9 and 10 illustrate a structure of a multifunction apparatusaccording to an embodiment of the present invention. FIGS. 9 and 10illustrate the scanner device 100 and a printing unit 70. The printingunit 70 according to the current embodiment is an electrophotographyprinting unit that prints an image on a sheet of paper by usingelectrophotography. The scanner device 100 is disposed above theprinting unit 70. Hereinafter, an example of the printing unit 70 willbe described.

A photosensitive drum 1, a charging roller 2, an exposure unit 10, adeveloping unit 20, and a transfer unit 30 are illustrated. Thephotosensitive drum 1 is an example of a photosensitive body on which anelectrostatic latent image is formed. The photosensitive drum 1 isconfigured by forming a photosensitive layer having photoconductivity ona perimeter of a cylindrical metallic pipe. The charging roller 2 is anexample of a charging unit that charges the surface of thephotosensitive drum 1 to a uniform potential. A charging bias voltage isapplied to the charging roller 2. A corona charging unit (not shown),instead of the charging roller 2, may also be used.

The exposure unit 10 scans light L that is modulated according to imageinformation on the surface of the photosensitive drum 1 charged to theuniform potential, thereby forming an electrostatic latent image. Alaser scanning unit (LSU) that scans light irradiated from a laser diodeon the photosensitive drum 1, for example, by deflecting the light in amain scanning direction by using a polygonal mirror, may be used as theexposure unit 10.

The developing unit 20 develops the electrostatic latent image formed onthe photosensitive drum 1 by supplying a toner to the electrostaticlatent image. The toner is accommodated in the developing unit 20. Thedeveloping unit 20 includes a developing roller 3 that is used todevelop the electrostatic latent image formed on the surface of thephotosensitive drum 1 into a visual toner image by supplying the tonerto the electrostatic latent image. In the current embodiment, anon-contact development method is used. The surface of the developingroller 3 is spaced apart from the surface of the photosensitive drum 1by a distance of about several hundreds of microns. The distance isreferred to as a development gap. When a development bias voltage isapplied to the developing roller 3, the toner is moved to theelectrostatic latent image formed on the surface of the photosensitivedrum 1 via the development gap. When a contact development method isused, the developing roller 3 contacts the photosensitive drum 1. Thedeveloping unit 20 may further include a supply roller 4 that attachesthe toner to the developing roller 3. A supply bias voltage may beapplied to the supply roller 4 so as to attach the toner to thedeveloping roller 3. Reference numeral 5 represents a regulation memberthat regulates the amount of the toner attached to the surface of thedeveloping roller 3. The regulation member 5 may be a regulation bladeof which a front end is attached to the developing roller 3 under apredetermined pressure, for example. Reference numeral 6 represents acleaning member that removes the remaining toner and a foreign substancefrom the surface of the photosensitive drum 1 before charging. Thecleaning member 6 may be a cleaning blade of which a front end contactsthe surface of the photosensitive drum 1. An agitator 7 conveys thetoner to the developing roller 3. The agitator 7 may agitate the tonerand may charge the toner to a predetermined potential.

The transfer roller 30 is an example of a transfer unit that is disposedto face the surface of the photosensitive drum 1 and forms a transfernip. A transfer bias voltage that is used to transfer the toner imagedeveloped on the surface of the photosensitive drum 1 onto a recordingmedium P is applied to the transfer roller 30. A coroner transfer unit,instead of the transfer roller 30, may also be used.

The recording medium P on which an image is to be printed is picked upby a pickup roller 42 from a paper-feeding cassette 41. The picked-uprecording medium P is supplied by the transfer roller 43 to a region inwhich the transfer roller 30 and the photosensitive drum 1 face eachother. Due to the transfer bias voltage applied to the transfer roller130, the toner image on the photosensitive drum 1 is transferred ontothe surface of the recording medium P and is maintained on the surfaceof the recording medium P due to an electrostatic attractive force.

A fusing unit 50 fuses the toner image on the recording medium P byheating and pressing the toner image, thereby forming a permanentprinted image on the recording medium P. The fusing unit 50 may form afusing nip when a heating roller 51 including a heating unit 53 and apressing roller 52 are engaged with each other, as illustrated inFIG. 1. The recording medium P is discharged by a discharge roller 44 toa discharge tray 205 after the recording medium P has passed through thefusing unit 50.

According to the multifunction apparatus illustrated in FIGS. 9 and 10,printing, copying, and scanning operations may be performed. Theprinting operation is an operation in which an image is printed on asheet of paper based on image information from an external host (notshown). The copying operation is an operation in which the imageinformation is read from a document by using the scanner device 100 andis transmitted to the printing unit 70 in order to print the image onthe sheet of paper. The scanning operation is an operation in which theimage information is read from the document and the read imageinformation is transmitted to the host (not shown), for example. When acommunication unit (not shown) is disposed, a facsimile transmissionfunction of transmitting the read image information by using acommunication line, such as a telephone line or the like, and afacsimile receiving function of printing the image information receivedvia the telephone line or the like by using the printing unit 70 may beperformed.

In the above embodiment, a single-color electrophotography printing unit70 including one developing unit 20 has been described. However, thepresent invention is not limited thereto. In case of a multi-colorelectrophotography printing unit, four developing units 20 in which cyan(C), magenta (M), yellow (Y), and black (K) color toners areaccommodated, may be used. In addition, the printing unit 70 may useother image forming methods, such as an inkjet method, a thermaltransfer method, and the like.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims.

What is claimed is:
 1. A scanner device comprising: a scanning path onwhich a scanning member for scanning an image from a document isdisposed; a supply path on which a document is supplied to the scanningpath; a discharge path on which a document is discharged after scanningof the document on the scanning path has been completed; and a re-supplypath that extended to the supply path from an intersection where thescanning path and the discharge path cross so that a document fed alongthe discharge path in a direction opposite to a document-feedingdirection is re-supplied to the supply path after scanning of one sideof the document has been completed, wherein one-side guide portions ofthe supply path, the discharge path, and the re-supply path areintegrally formed.
 2. The scanner device of claim 1, wherein theone-side guide portions of the supply path, the discharge path, and there-supply path are integrally formed by using injection molding.
 3. Thescanner device of claim 2, further comprising: an upper frame; a baseframe; and a main frame interposed between the base frame and the upperframe, and integrally formed with the one-side guide portions of thesupply path, the discharge path, and the re-supply path by using plasticinjection molding.
 4. The scanner device of claim 3, wherein theone-side guide portions comprises a lower supply guide portion, a lowerdischarge guide portion, and a lower re-supply guide portion forminglower guides of the supply path, the discharge path, and the re-supplypath, respectively.
 5. The scanner device of claim 4, wherein the upperframe comprises an upper guide portion that faces the first re-supplyguide portion and the first discharge guide portion and forms there-supply path and the discharge path, and an upper supply guide portionthat faces the lower supply guide portion and forms the supply path. 6.The scanner device of claim 5, wherein an end part of the lowerre-supply guide portion that is directed towards the discharge path isstepped from an end part of the lower discharge guide portion that isdirected towards the re-supply path so that a document fed along thedischarge path in a direction opposite to a document-feeding directionis guided to the re-supply path.
 7. The scanner device of claim 1,further comprising: a pressing member for pressing a document againstthe scanning member, wherein the pressing member is disposed facing ascanning window in a position above the scanning member so that thedocument is secured in contact with the scanning window, and forms anupper guide of the scanning path.
 8. The scanner device of claim 1,further comprising: at least one actuator that is rotated in contactwith a fed document; and at least one document sensor for detectingrotation of the actuator and generating an electrical signal, whereinthe at least one document sensor is disposed in a region outside of adocument-feeding region in a widthwise direction of a document.
 9. Thescanner device of claim 8, further comprising a control unit forcontrolling an operation of feeding a document, wherein the control unitis disposed in the region outside of the document-feeding region. 10.The scanner device of claim 8, further comprising: a main frameintegrally formed with the one-side guide portions of the supply path,the discharge path, and the re-supply path by using plastic injectionmolding, wherein at least one of the at least one document sensor isdisposed in a sidewall of the main frame in the region outside of thedocument-feeding region.
 11. A multifunction apparatus comprising: aprinting unit for printing an image on a sheet of paper; a scannerdevice comprising: a scanning path on which a scanning member forscanning an image from a document is disposed; a supply path on which adocument is supplied to the scanning path; a discharge path on which adocument is discharged after scanning of the document on the scanningpath has been completed; and a re-supply path that extended to thesupply path from an intersection where the scanning path and thedischarge path cross so that a document fed along the discharge path ina direction opposite to a document-feeding direction is re-supplied tothe supply path after scanning of one side of the document has beencompleted, wherein one-side guide portions of the supply path, thedischarge path, and the re-supply path are integrally formed.
 12. Themultifunction apparatus of claim 11, wherein the one-side guide portionsof the supply path, the discharge path, and the re-supply path areintegrally formed by using injection molding.
 13. The multifunctionapparatus of claim 12, further comprising: an upper frame; a base frame;and a main frame interposed between the base frame and the upper frame,and integrally formed with the one-side guide portions of the supplypath, the discharge path, and the re-supply path by using plasticinjection molding.
 14. The multifunction apparatus of claim 13, whereinthe one-side guide portions comprises a lower supply guide portion, alower discharge guide portion, and a lower re-supply guide portionforming lower guides of the supply path, the discharge path, and there-supply path, respectively.
 15. The multifunction apparatus of claim14, wherein the upper frame comprises an upper guide portion that facesthe first re-supply guide portion and the first discharge guide portionand forms the re-supply path and the discharge path, and an upper supplyguide portion that faces the lower supply guide portion and forms thesupply path.
 16. The multifunction apparatus of claim 15, wherein an endpart of the lower re-supply guide portion that is directed towards thedischarge path is stepped from an end part of the lower discharge guideportion that is directed towards the re-supply path so that a documentfed along the discharge path in a direction opposite to adocument-feeding direction is guided to the re-supply path.
 17. Themultifunction apparatus of claim 11, further comprising: a pressingmember for pressing a document against the scanning member, wherein thepressing member is disposed facing a scanning window in a position abovethe scanning member so that the document is secured in contact with thescanning window, and forms an upper guide of the scanning path.
 18. Themultifunction apparatus of claim 11, further comprising: at least oneactuator that is rotated in contact with a fed document; and at leastone document sensor for detecting rotation of the actuator andgenerating an electrical signal, wherein the at least one documentsensor is disposed in a region outside of a document-feeding region in awidthwise direction of a document.
 19. The multifunction apparatus ofclaim 18, further comprising a control unit for controlling an operationof feeding a document, wherein the control unit is disposed in theregion outside of the document-feeding region.
 20. The multifunctionapparatus of claim 18, further comprising: a main frame integrallyformed with the one-side guide portions of the supply path, thedischarge path, and the re-supply path by using plastic injectionmolding, wherein at least one of the at least one document sensor isdisposed in a sidewall of the main frame in the region outside of thedocument-feeding region.